Chocks, Chocking and CHOCKFAST® - Marine Chock Installation Presented byITW Philadelphia Resins Presentation Outline Basic Chocking Procedure Special Chocking Situations Some Chocking “Do’s & Don’ts” For More Information Basic Chocking Procedure How to Chock a Marine Engine Step-by-Step 1. Determine Chock Volume Before the chocking job starts, develop a Chocking Plan. Determine the total volume of all chocks including the overpour areas and subtracting the volume taken up by the bolts. 4 kg (7. leaks.5 lbs) = 1966 cm3 (120 in3) 6.8 kg (15 lbs) = 4261 cm3 (260 in3) .Order Chockfast Early Be sure to have at least 10% more Chockfast Orange than required in case of spills. etc. 3. 2. Gather Materials Supplied by ITW PRC – Chockfast Orange – Open-cell Foam – Release Agent – Jiffy Mixing Blades – Non-melt Grease – Strip Caulking / Putty – PRT-51 Solvent Supplied by Shipyard – 1/2” Drill Motor – Metal Dams – Safety Glasses – Disposable Vinyl Gloves – Surface Thermometer – Foam-backed Tape . 3. . Pre-condition the Chockfast Pre-condition the Chockfast Resin and hardener by storing it at 20oC to 25oC (68oF to 77oF) for at least 12 hours before use to ensure the epoxy will mix well and pour easily. paint. and rust so that Chockfast makes complete contact with the foundation and bedplate. . Clean Thoroughly Clean all surfaces of oil. grease. It is also very important to remove all burrs and welding slag. millscale.4. Open-cell foam allows air to escape through it. . Insert Foam Dam Insert flexible damming along the back and on either side of the chock.5. Open-cell foam is best but neoprene can also be used. The foam should fit tightly between the steel to prevent the Chockfast from leaking. A 6 mm (1/4 inch) press fit on the foam work best on soft foam.Insert Foam Dam A wood stick is a good tool for inserting foam. . Be careful not to tear the foam. Trim Ends of Foam Check to ensure that the damming is not twisted and is firmly in place. Cut off the protruding ends 25 mm (1 inch) from the engine bed plate. .6. Spray With Release Agent Only a very light spray is needed.7. . The steel should NOT be wet with Release Agent. 8. Prepare to Plug The Bolt Hole Prepare to plug hole with either a greased bolt. an Armaflex tubing covered bolt. . a greased wooden plug or a wooden dowel covered with foam tubing. Bolt covered with grease Foam or tape wrapped bolt Grease covered wood dowel Foam covered wood dowel Always use non-melt grease. . Insert Plug/Bolt into the Hole The plug or bolt must prevent the Chockfast from leaking out from around the bolt hole. install the nut hand-tight only.9. If using a bolt. 10.6 mm thick flat bar or angle iron. . The flat bar must be high enough to allow the Chockfast to be filled a minimum of 15 mm higher than the bottom of the bedplate. 12 to 18 mm from the bedplate. Install the Front Dam Create a front dam by tack welding a 4 . Seal the flat bar with putty or caulking. The front dam MUST be made of metal. 11. Using putty. caulking or Silicone. . The foam can be press-fit into place or glued using contact cement. Seal the Chock Mold Insert a piece of foam damming material at the front corners to prevent the Chockfast from overflowing. seal all potential leak points. 12. . Spray the Front Dam Spray Release Agent on the inside of the front dam. Also spray Release Agent on top of the steel all around the front dam to make clean up easier. use heaters to raise the temperature of the steel above 21oC (70oF) after the Chockfast has gelled for 24 hours. If the steel temperature is below 13oC (55oF). Only when everything is ready should the Chockfast be brought out of storage and taken to the job site. Measure the temperature of the steel and check the thickness of the chocks. .13. Final Check Inspect all dams to ensure they are complete and well sealed. 14. Example: 20oC steel + 57 mm chock thickness = 1/2 Hardener Reduction . Determine Required Hardener Using the Hardener Ratio Guide determine the correct amount of hardener to add to the resin. 15. Turn the bottle of Hardener upside down and squeeze the amount of hardener called for in the Hardener Ratio Guide into the resin. Puncture the paper seal under the bottle cap on the hardener. Full Reduction = Squeeze in all BUT this amount of hardener 3/4 Reduction = Squeeze in all BUT this amount of hardener 1/2 Reduction = Squeeze in all BUT this amount of hardener 1/4 Reduction = Squeeze in all BUT this amount of hardener NO Reduction = Use ALL of the hardener . Squeeze Hardener into Resin Put on rubber gloves and eye protection. Mix the Resin & Hardener Use a Jiffy Mixing blade or similar type mixing blade and a variable speed drill motor. Place the mixing blade all the way into the Chockfast and keep the blade submerged. Hold the can of Chockfast securely between your feet.16. Start mixing very slowly. Mix for 3 minutes. traversing the can. Make sure the bottom of the can is scoured. . Gradually increase the speed of the mixing blade but do not exceed 300 RPM. 17. A thin stream of Chockfast will force the air bubbles out of the mixture. Pour Chockfast Pour Chockfast slowly. . from a height of about 300 mm (12 inches). in a thin stream. . DO NOT scrape residue from the bottom or sides of the can.Pouring Chockfast Pour the Chockfast into the lowest corner of the overpour area. Pour it slowly and steadily into this one corner only. They can appear at any time.18. Do not leave until the chocks are hard. Fill Chock Molds Fill the overpour area until the top of the Chockfast is at least 12 mm (½ inch) above the bottom of the engine bed plate. . Continually check for leaks. The time required to cure depends on the steel temperature.18oC (55oF .65oF) 19oC . Curing Allow the Chockfast to fully cure.21oC (66oF .19. 48 Hours 24 Hours 18 Hours 13oC .70oF) Above 21oC (70oF) . Bevel the outside edge of the Chockfast removing the sharp edge using a grinder or sanding disc. Gently pry it away from the Chockfast.20. Clean Up Wait until the Chockfast has completely cured before removing the outer metal dam. . 21. . Back Out All Jacking Screws Remove all Jacking Screws or back them out 4 turns. fill holes. If screws are removed. RT LL = Righty Tighty .22. back out all jacking bolts and remove all alignment devices. Torque Down Bolts First. Then torque down all mounting bolts per engine manufacturer’s instructions or contact ITW Philadelphia Resins.Lefty Loosey . Special Chocking Situations and How to Handle Them . .Creating a Fitted Bolt Spray the bolt with Release Agent. Center the bolt in the hole and make sure it has 1/8 to 3/8 inch clearance. Seal the bottom of the bolt so it will not leak. Fill chock area with Chockfast up to top of the bolt hole. Jacking Screws Whenever possible. If a jacking screw does fall inside a chock. do not pour Chockfast around a jacking screw. wrap it with foam-backed tape. cover with Armaflex pipe insulation or coat with non-melt grease . Pour successive layers within 4 to 6 hours. Use Layer Keys to prevent the edges from curling between pours. .Chocking In Layers The Hardener Ratio Guide sometimes calls for making “Layered Pours” of Chockfast because the Chockfast may overheat if poured in a single layer. Chocking with Limited Access Chockfast Orange can be injected with a grease gun The outer metal dam can be installed at an angle . Some Chocking Do’s & Don’ts How to be more successful . DO Fill Up the Overpour 12mm Minimum . DON’T Chock Around a Corner Do NOT pour Chockfast around a corner. . It will always lead to cracking because the corner acts like a wedge. .DO Round All Corners & Edges When creating the chock mold. it is a good idea to round all corners and edges that may protrude into the Chockfast. This lessens the chance of cracking. DON’T Make the Overpour Too Large The Chockfast in the overpour area must remain cool and liquid to feed material back under the engine bed if needed. . the overpour must be small and kept cool with a heavy metal front dam. To do this. Just top off the overpour area with some more Chockfast. Do not be concerned about this.DO Top off All Chocks Sometimes the inside edge of the overpour will be drawn down slightly. . .DON’T Remove the Dams Until the Chockfast Has Fully Cured Wait until the Chockfast has cured completely before removing the front metal dam or you could break the chock. DO Prepare for Leaks Have non-hardening putty on hand for sealing small leaks that may appear. . It is also a good idea to spray all areas adjacent to a chock with Release Agent to make clean up easier. DON’T Add Heat to A Chock Until the Chockfast Has Gelled . DO Pour Alternate Chocks If overheating the Chockfast is a concern. . wait until they are cool then fill the remainder of the chocks. fill every other chock. DON’T Forget the Release Agent . DO Make Sure the Dams Will Not Move . Watch Out For MAN B&W Engines . For More Information Where to go for help . Technical Bulletins TB 692 General Guidelines for Designing Marine Chocks TB 659 Physical Properties of Chockfast Orange TB 656 Physical Properties of Chockfast Gray .